1 //===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the MapValue function, which is shared by various parts of
11 // the lib/Transforms/Utils library.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Transforms/Utils/ValueMapper.h"
16 #include "llvm/BasicBlock.h"
17 #include "llvm/Constants.h"
18 #include "llvm/GlobalValue.h"
19 #include "llvm/Instruction.h"
20 #include "llvm/LLVMContext.h"
21 #include "llvm/MDNode.h"
22 #include "llvm/ADT/SmallVector.h"
25 Value *llvm::MapValue(const Value *V, ValueMapTy &VM, LLVMContext *Context) {
26 Value *&VMSlot = VM[V];
27 if (VMSlot) return VMSlot; // Does it exist in the map yet?
29 // NOTE: VMSlot can be invalidated by any reference to VM, which can grow the
30 // DenseMap. This includes any recursive calls to MapValue.
32 // Global values do not need to be seeded into the ValueMap if they are using
33 // the identity mapping.
34 if (isa<GlobalValue>(V) || isa<InlineAsm>(V))
35 return VMSlot = const_cast<Value*>(V);
37 if (Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V))) {
38 if (isa<ConstantInt>(C) || isa<ConstantFP>(C) ||
39 isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) ||
40 isa<UndefValue>(C) || isa<MDString>(C))
41 return VMSlot = C; // Primitive constants map directly
42 else if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
43 for (User::op_iterator b = CA->op_begin(), i = b, e = CA->op_end();
45 Value *MV = MapValue(*i, VM, Context);
47 // This array must contain a reference to a global, make a new array
50 std::vector<Constant*> Values;
51 Values.reserve(CA->getNumOperands());
52 for (User::op_iterator j = b; j != i; ++j)
53 Values.push_back(cast<Constant>(*j));
54 Values.push_back(cast<Constant>(MV));
55 for (++i; i != e; ++i)
56 Values.push_back(cast<Constant>(MapValue(*i, VM, Context)));
57 return VM[V] = Context->getConstantArray(CA->getType(), Values);
62 } else if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
63 for (User::op_iterator b = CS->op_begin(), i = b, e = CS->op_end();
65 Value *MV = MapValue(*i, VM, Context);
67 // This struct must contain a reference to a global, make a new struct
70 std::vector<Constant*> Values;
71 Values.reserve(CS->getNumOperands());
72 for (User::op_iterator j = b; j != i; ++j)
73 Values.push_back(cast<Constant>(*j));
74 Values.push_back(cast<Constant>(MV));
75 for (++i; i != e; ++i)
76 Values.push_back(cast<Constant>(MapValue(*i, VM, Context)));
77 return VM[V] = Context->getConstantStruct(CS->getType(), Values);
82 } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
83 std::vector<Constant*> Ops;
84 for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i)
85 Ops.push_back(cast<Constant>(MapValue(*i, VM, Context)));
86 return VM[V] = CE->getWithOperands(Ops);
87 } else if (ConstantVector *CP = dyn_cast<ConstantVector>(C)) {
88 for (User::op_iterator b = CP->op_begin(), i = b, e = CP->op_end();
90 Value *MV = MapValue(*i, VM, Context);
92 // This vector value must contain a reference to a global, make a new
93 // vector constant and return it.
95 std::vector<Constant*> Values;
96 Values.reserve(CP->getNumOperands());
97 for (User::op_iterator j = b; j != i; ++j)
98 Values.push_back(cast<Constant>(*j));
99 Values.push_back(cast<Constant>(MV));
100 for (++i; i != e; ++i)
101 Values.push_back(cast<Constant>(MapValue(*i, VM, Context)));
102 return VM[V] = Context->getConstantVector(Values);
107 } else if (MDNode *N = dyn_cast<MDNode>(C)) {
108 for (MDNode::const_elem_iterator b = N->elem_begin(), i = b,
109 e = N->elem_end(); i != e; ++i) {
112 Value *MV = MapValue(*i, VM, Context);
114 // This MDNode must contain a reference to a global, make a new MDNode
116 SmallVector<Value*, 8> Values;
117 Values.reserve(N->getNumElements());
118 for (MDNode::const_elem_iterator j = b; j != i; ++j)
119 Values.push_back(*j);
120 Values.push_back(MV);
121 for (++i; i != e; ++i)
122 Values.push_back(MapValue(*i, VM, Context));
123 return VM[V] = Context->getMDNode(Values.data(), Values.size());
129 assert(0 && "Unknown type of constant!");
136 /// RemapInstruction - Convert the instruction operands from referencing the
137 /// current values into those specified by ValueMap.
139 void llvm::RemapInstruction(Instruction *I, ValueMapTy &ValueMap) {
140 for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) {
141 Value *V = MapValue(*op, ValueMap, I->getParent()->getContext());
142 assert(V && "Referenced value not in value map!");